Example: Combine Factor Levels Using levels () Function In this example, I'll illustrate how to merge two factor levels into one category using the levels function in R. I have a column of data that is a factor with levels A, B and C, I am interested in combining two of these levels into one factor, so it would become A and B, with B = B and C, or maybe a new varia. In this approach to group factor levels, the user has to simply call the levels () functions with the required parameters as required by the user, and then it will be leading to the new factor level as specified by the user in other words we will be merging two.
New levels are constructed by concatenating the levels with `sep` as a separator. This is useful when comparing ordinal regression with polytomous (multinomial) regression and there are too many categories for polytomous regression. `combine.levels` is also useful when assumptions of ordinal models are being checked empirically by computing.
combine.levels Description Combine Infrequent Levels of a Categorical Variable Usage combine.levels(x, minlev = 0.05, m, ord = is.ordered(x), plevels = FALSE, sep = ",") Arguments Details After turning 'x' into a 'factor' if it is not one already, combines levels of 'x' whose frequency falls below a specified relative frequency 'minlev. An R data frame can have numeric as well as factor variables. It has been seen that, factor levels in the raw data are recorded as synonyms even in different language versions but it is rare.
For example, a factor variable can have hot and cold as levels but it is possible that hot is recorded as garam by a Hindi native speaker because garam is Hindi form of hot. Therefore, we need to combine. This makes it easy to put levels together and create a new factor variable.
If a factor variable is currently coded with levels c ("Male","Female","Man", "M"), and the user needs to combine the redundant levels for males, this is the function to use! combineLevels: Combine levels of given factors Description combineLevels combines levels of given factors and applies this levels to given factors. This eases the work with factors since all factors have the same levels.
Usage combineLevels(x, apply=TRUE, drop=FALSE) Arguments. Wondering if anyone has run across a package/function in R that will combine levels of a factor whose proportion of all the levels in a factor is less than some threshold? Specifically, one of the. Combines levels from two columns into new level stored into a new column.
Allows users to create new classifications using levels defined in existing fields.
